Brain mechanisms linking language and action

The Mind Hidden in Our Hands

Our hands are always with us and are used for communication all over the world. When children do not have an established language model to learn from, they use their hands to gesture, and these gestures take on the forms of language. In this role, the hands reveal the fundamental properties of the mind that give shape to language. When children do learn an established language, they again use their hands to gesture. These gestures do not look like language but form an integrated system with language. In this role, the hands can convey ideas not found in the language they accompany. In both contexts, gesture provides a clear view of the mind hidden in our hands.

Enhancement of perceptual and cognitive functions in near-death experience: A perspective from embodiment theories

The phenomenon of near-death experience (NDE) is attracting a growing attention among researchers of various fields. In this study, we looked at NDE from a cognitive perspective to find out how NDE events are embodied when people recall and describe them. We examined the descriptions of a group of people talking about what they had experienced in the state of NDE. Based on the gesture-as-simulated-action theory, we assumed that co-speech gestures occurring when people were talking about their experiences were physical realizations of mentally-simulated events. The results showed that the number of iconic and metaphoric gestures occurring with expressions referring to NDE events was significantly larger than those occurred with expressions referring to ordinary events. Based on these results, we suggest that embodied memory for NDE events is stronger than embodied memory for ordinary non-NDE events. NDE events are perceived, recalled, and embodied by strong activation of sensorimotor systems in a state of perceptual and cognitive enhancement, although sensorimotor systems seem to be unresponsive to sensory stimuli during NDE. Finally, based on theories of embodied cognition, we conclude that the enhancement of cognitive functions that takes place in the state of NDE is the result of enhancement in perceptual functions.

Effect of gender matching and attentional focus on the link between action observation and action verb processing

Several studies have demonstrated the existence of a link between action observation (AO) and language. However, the optimizing parameters for this link have not been explored until now. To answer this question, the present study proposed two experiments for assessing the role of motor repertory and attentional focus. Sixty participants performed a priming task in which they had to decide if a verb was or was not an action verb after they saw a point-light display (PLD) representing an action. Only one difference distinguished the experiments. In experiment one, the PLD was either in accordance or not with the gender kinematics of the observer, whereas in the second experiment, the PLD either focused on or was unfocused on the main limbs implied in the action. The results show that motor repertory affects the link between action observation and action verb processing, whereas attentional focus does not. Implications of these results are highlighted in the discussion, notably to better understand the mechanisms that explain the link between action observation and action verb processing.

A new ontology for numerical cognition: Integrating evolutionary, embodied, and data informatics approaches

Numerical cognition is a field that investigates the sociocultural, developmental, cognitive, and biological aspects of mathematical abilities. Recent findings in cognitive neuroscience suggest that cognitive skills are facilitated by distributed, transient, and dynamic networks in the brain, rather than isolated functional modules. Further, research on the bodily and evolutionary bases of cognition reveals that our cognitive skills harness capacities originally evolved for action and that cognition is best understood in conjunction with perceptuomotor capacities. Despite these insights, neural models of numerical cognition struggle to capture the relation between mathematical skills and perceptuomotor systems. One front to addressing this issue is to identify building block sensorimotor processes (BBPs) in the brain that support numerical skills and develop a new ontology connecting the sensorimotor system with mathematical cognition. BBPs here are identified as sensorimotor functions, associated with distributed networks in the brain, and are consistently identified as supporting different cognitive abilities. BBPs can be identified with new approaches to neuroimaging; by examining an array of sensorimotor and cognitive tasks in experimental designs, employing data-driven informatics approaches to identify sensorimotor networks supporting cognitive processes, and interpreting the results considering the evolutionary and bodily foundations of mathematical abilities. New empirical insights on the BBPs can eventually lead to a revamped embodied cognitive ontology in numerical cognition. Among other mathematical skills, numerical magnitude processing and its sensorimotor origins are discussed to substantiate the arguments presented. Additionally, an fMRI study design is provided to illustrate the application of the arguments presented in empirical research.

The value of action observation in speech and language rehabilitation: A systematic review and meta-analysis

In this systematic review and meta-analysis, our aim was to identify and quantify evidence of action observation therapy (AOT) efficacy in managing language deficits in patients with aphasia. This study conducts two quantitative investigations: firstly, comparing the effects of AOT and conventional control therapy in different groups, and secondly, analyzing within AOT group to explore potential moderators of AOT effectiveness. Four databases were searched up until August 2023 to find studies utilizing AOT for aphasia management. Seven eligible studies were included. The main analyses revealed moderate evidence of improvement in naming tasks, with a large effect size (Hedge's g = 1.27, 95 %CI [0.44; 2.09], p = 0.003, I2 < 25) following AOT compared to control interventions. Furthermore, to be efficient, AOT should focus on human actions (e.g., running, jumping) rather than non-human actions (e.g., meowing or barking). These findings indicate that AOT is a promising alternative complementary approach for patients with aphasia. Future research should confirm the potential benefits of AOT with more randomized controlled studies and aim to clarify the minimal dose necessary and the possibility of transfer to various language tasks.

Sensitivity and specificity of the action observation network to kinematics, target object, and gesture meaning

Hierarchical models have been proposed to explain how the brain encodes actions, whereby different areas represent different features, such as gesture kinematics, target object, action goal, and meaning. The visual processing of action-related information is distributed over a well-known network of brain regions spanning separate anatomical areas, attuned to specific stimulus properties, and referred to as action observation network (AON). To determine the brain organization of these features, we measured representational geometries during the observation of a large set of transitive and intransitive gestures in two independent functional magnetic resonance imaging experiments. We provided evidence for a partial dissociation between kinematics, object characteristics, and action meaning in the occipito-parietal, ventro-temporal, and lateral occipito-temporal cortex, respectively. Importantly, most of the AON showed low specificity to all the explored features, and representational spaces sharing similar information content were spread across the cortex without being anatomically adjacent. Overall, our results support the notion that the AON relies on overlapping and distributed coding and may act as a unique representational space instead of mapping features in a modular and segregated manner.

Using Biosensors to Detect and Map Language Areas in the Brain for Individuals with Traumatic Brain Injury

The application of biosensors in neurolinguistics has significantly advanced the detection and mapping of language areas in the brain, particularly for individuals with brain trauma. This study explores the role of biosensors in this domain and proposes a conceptual model to guide their use in research and clinical practice. The researchers explored the integration of biosensors in language and brain function studies, identified trends in research, and developed a conceptual model based on cluster and thematic analyses. Using a mixed-methods approach, we conducted cluster and thematic analyses on data curated from Web of Science, Scopus, and SciSpace, encompassing 392 articles. This dual analysis facilitated the identification of research trends and thematic insights within the field. The cluster analysis highlighted Functional Magnetic Resonance Imaging (fMRI) dominance and the importance of neuroplasticity in language recovery. Biosensors such as the Magnes 2500 watt-hour (WH) neuromagnetometer and microwire-based sensors are reliable for real-time monitoring, despite methodological challenges. The proposed model synthesizes these findings, emphasizing biosensors' potential in preoperative assessments and therapeutic customization. Biosensors are vital for non-invasive, precise mapping of language areas, with fMRI and repetitive Transcranial Magnetic Stimulation (rTMS) playing pivotal roles. The conceptual model serves as a strategic framework for employing biosensors and improving neurolinguistic interventions. This research may enhance surgical planning, optimize recovery therapies, and encourage technological advancements in biosensor precision and application protocols.

The Evolution of Symbolic Thought: At the Intersection of Schizophrenia Psychopathology, Ethnoarchaeology, and Neuroscience

The human capacity for symbolic representation arises, evolutionarily and developmentally, from the exploitation of a widespread sensorimotor network, along a fundamental continuity between embodied and symbolic modes of experience. In this regard, the fine balancing between constrained sensorimotor connections (responsible for self-embodiment processing) and more untethered neural associations (responsible for abstract and symbolic processing) is context dependent and plastically neuromodulated, thus intersubjectively constructed within a specific socio-cultural milieu. Instead, in the schizophrenia spectrum this system falls off catastrophically, due to an unbalance toward too unconstrained sensorimotor connectivity, leading to a profound distortion of self/world relation with a symbolic activity detached from its embodied ground. For this very reason, however, schizophrenia psychopathology may contribute to unveil, in a distorted or magnified way, ubiquitous structural features of human symbolic activity, beneath the various, historically determined cultural systems. In this respect, a comparative approach, linking psychopathology and ethnoarchaeology, allows highlight the following invariant formal characteristics of symbolic processing: (1) Emergence of salient perceptive fragments, which stand out from the perceptual field. (2) Spreading of a multiplicity of new significances with suspension of common-sense meaning. (3) Dynamic and passive character through which meaning proliferation is experienced. This study emphasizes the importance of fine-grained psychopathology to elucidate, within a cross-disciplinary framework, the evolutionarily and developmental pathways that shape the basic structures of human symbolization.

Long-term motor training enhances functional connectivity between semantic and motor regions in an effector-specific manner: evidence from elite female football athletes

The relation between the action verb semantic processing and sensorimotor experience remains controversial. In this study, we examined whether plasticity changes in brain are specifically related to semantic processing of foot action verbs when long-term motor training is mainly aimed at the foot. To address this question, we acquired resting-state functional magnetic resonance imaging scans and behavioral data from a verb two-choice task from female expertise football players and football novices. We compared the resting-state functional connectivity (rsFC) differences between experts and novices using motor execution regions and general semantic regions (left anterior temporal lobe, lATL) as seed, and explored the neural correlates of behavioral performance. Here, the drift rate (v) parameter of the drift diffusion model (DDM) was used to capture the semantic processing capability. We found experts showed increased correlation between lATL subregions and important brain regions for motor processing, including supplementary motor area (SMA), bilateral paracentral lobule (PL), superior parietal lobule and inferior parietal lobule, in contrast to novices. Further predictive model analysis showed the FC found in rsFC analysis can significantly predict drift rate of foot action verb in both experts and novices, but not drift rate of hand action verb. Our findings therefore establish a connection between effector-related semantic processing and the plasticity changes in brain functional connectivity, attributable to long-term foot-related motor training. This provides evidence supporting the view that semantic processing is fundamentally rooted in the sensorimotor system.

The Neural Correlates of Embodied L2 Learning: Does Embodied L2 Verb Learning Affect Representation and Retention?

We investigated how naturalistic actions in a highly immersive, multimodal, interactive 3D virtual reality (VR) environment may enhance word encoding by recording EEG in a pre/post-test learning paradigm. While behavior data have shown that coupling word encoding with gestures congruent with word meaning enhances learning, the neural underpinnings of this effect have yet to be elucidated. We coupled EEG recording with VR to examine whether embodied learning improves learning and creates linguistic representations that produce greater motor resonance. Participants learned action verbs in an L2 in two different conditions: specific action (observing and performing congruent actions on virtual objects) and pointing (observing actions and pointing to virtual objects). Pre- and post-training participants performed a match-mismatch task as we measured EEG (variation in the N400 response as a function of match between observed actions and auditory verbs) and a passive listening task while we measured motor activation (mu [8-13 Hz] and beta band [13-30 Hz] desynchronization during auditory verb processing) during verb processing. Contrary to our expectations, post-training results revealed neither semantic nor motor effects in either group when considered independently of learning success. Behavioral results showed a great deal of variability in learning success. When considering performance, low performance learners showed no semantic effect and high performance learners exhibited an N400 effect for mismatch versus match trials post-training, independent of the type of learning. Taken as a whole, our results suggest that embodied processes can play an important role in L2 learning.

Narrative analysis in individuals with Parkinson's disease following intensive voice treatment: secondary outcome variables from a randomized controlled trial

Communication is often impaired in individuals with Parkinson's disease (PD), typically secondary to sensorimotor deficits impacting voice and speech. Language may also be diminished in PD, particularly for production and comprehension of verbs. Evidence exists that verb processing is influenced by motor system modulation suggesting that verb deficits in PD are underpinned by similarities in the neural representations of actions that span motor and semantic systems. Conversely, subtle differences in cognition in PD may explain difficulty in processing of complex syntactic forms, which increases cognitive demand and is linked to verb use. Here we investigated whether optimizing motor system support for vocal function (improving loudness) affects change in lexical semantic, syntactic, or informativeness aspects of spoken discourse. Picture description narratives were compared for 20 Control participants and 39 with PD, 19 of whom underwent Lee Silverman Voice Treatment (LSVT LOUD®). Treated PD narratives were also contrasted with those of untreated PD and Control participants at Baseline and after treatment. Controls differed significantly from the 39 PD participants for verbs per utterance, but this difference was largely driven by untreated PD participants who produced few utterances but with verbs, inflating their verbs per utterance. Given intervention, there was a significant increase in vocal loudness but no significant changes in language performance. These data do not support the hypothesis that targeting this speech motor system results in improved language production. Instead, the data provide evidence of considerable variability in measures of language production across groups, particularly in verbs per utterance.

No support for a causal role of primary motor cortex in construing meaning from language: An rTMS study

Embodied cognition theories predict a functional involvement of sensorimotor processes in language understanding. In a preregistered experiment, we tested this idea by investigating whether interfering with primary motor cortex (M1) activation can change how people construe meaning from action language. Participants were presented with sentences describing actions (e.g., "turning off the light") and asked to choose between two interpretations of their meaning, one more concrete (e.g., "flipping a switch") and another more abstract (e.g., "going to sleep"). Prior to this task, participants' M1 was disrupted using repetitive transcranial magnetic stimulation (rTMS). The results yielded strong evidence against the idea that M1-rTMS affects meaning construction (BF01 > 30). Additional analyses and control experiments suggest that the absence of effect cannot be accounted for by failure to inhibit M1, lack of construct validity of the task, or lack of power to detect a small effect. In sum, these results do not support a causal role for primary motor cortex in building meaning from action language.

Embodiment and gestural realization of ergative verbs

In this study, we examined the gestural embodiment of active, passive, and active-form/passive-sense voices of ergative verbs in English. We analyzed gestures produced by presenters talking about a variety of subjects in a set of videos. We used several Chi-square tests to find out what type of gesture (representational, beat, and pointing gestures) co-occurred more frequently with active, passive, and active-form/passive-sense voices of ergative verbs. The results showed that representational gestures occurred more frequently with active than passive and active-form/passive-sense voices of ergative verbs. Furthermore, representational gestures occurred more frequently with active voices of ergative verbs having human subjects than non-human subjects. This was also the case with active-form/passive-sense sentences. Based on these results, it is suggested that form of a sentence is an influential factor in the process of embodying the situation that is described by that sentence. Active voice of an English ergative verb is more likely to be accompanied by representational gestures and is embodied more strongly than passive and active-form/passive-sense voices of that verb.

A Multivariate analysis on evoked components of Chinese semantic congruity: an OP-MEG study with EEG

The application of wearable magnetoencephalography using optically-pumped magnetometers has drawn extensive attention in the field of neuroscience. Electroencephalogram system can cover the whole head and reflect the overall activity of a large number of neurons. The efficacy of optically-pumped magnetometer in detecting event-related components can be validated through electroencephalogram results. Multivariate pattern analysis is capable of tracking the evolution of neurocognitive processes over time. In this paper, we adopted a classical Chinese semantic congruity paradigm and separately collected electroencephalogram and optically-pumped magnetometer signals. Then, we verified the consistency of optically-pumped magnetometer and electroencephalogram in detecting N400 using mutual information index. Multivariate pattern analysis revealed the difference in decoding performance of these two modalities, which can be further validated by dynamic/stable coding analysis on the temporal generalization matrix. The results from searchlight analysis provided a neural basis for this dissimilarity at the magnetoencephalography source level and the electroencephalogram sensor level. This study opens a new avenue for investigating the brain's coding patterns using wearable magnetoencephalography and reveals the differences in sensitivity between the two modalities in reflecting neuron representation patterns.

Regionally specific cortical lateralization of abstract and concrete verb processing: Magnetic mismatch negativity study

The neural underpinnings of processing concrete and abstract semantics remain poorly understood. Previous fMRI studies have shown that multimodal and amodal neural networks respond differentially to different semantic types; importantly, abstract semantics activates more left-lateralized networks, as opposed to more bilateral activity for concrete words. Due to the lack of temporal resolution, these fMRI results do not allow to easily separate language- and task-specific brain responses and to disentangle early processing stages from later post-comprehension phenomena. To tackle this, we used magnetoencephalography (MEG), a time-resolved neuroimaging technique, in combination with a task-free oddball mismatch negativity (MMN) paradigm, an established approach to tracking early automatic activation of word-specific memory traces in the brain. We recorded the magnetic MMN responses in 30 healthy adults to auditorily presented abstract and concrete action verbs to assess lateralization of word-specific lexico-semantic processing in a set of neocortical areas. We found that MMN responses to these stimuli showed different lateralization patterns of activity in the upper limb motor area (BA4) and parts of Broca's area (BA45/BA47) within ∼100-350 ms after the word disambiguation point. Importantly, the greater leftward response lateralization for abstract semantics was due to the lesser involvement of the right-hemispheric homologues, not increased left-hemispheric activity. These findings suggest differential region-specific involvement of bilateral sensorimotor systems already in the early automatic stages of processing abstract and concrete action semantics.

Experiential grounding of abstract concepts: Processing of abstract mental state concepts engages brain regions involved in mentalizing, automatic speech, and lip movements

concepts like mental state concepts lack a physical referent, which can be directly perceived. Classical theories therefore claim that abstract concepts require amodal representations detached from experiential brain systems. However, grounded cognition approaches suggest an involvement of modal experiential brain regions in the processing of abstract concepts. In the present functional magnetic resonance imaging study, we investigated the relation of the processing of abstract mental state concepts to modal experiential brain systems in a fine-grained fashion. Participants performed lexical decisions on abstract mental state as well as on verbal association concepts as control category. Experiential brain systems related to the processing of mental states, generating verbal associations, automatic speech as well as hand and lip movements were determined by corresponding localizer tasks. Processing of abstract mental state concepts neuroanatomically overlapped with activity patterns associated with processing of mental states, generating verbal associations, automatic speech and lip movements. Hence, mental state concepts activate the mentalizing brain network, complemented by perceptual-motor brain regions involved in simulation of visual or action features associated with social interactions, linguistic brain regions as well as face-motor brain regions recruited for articulation. The present results provide compelling evidence for the rich grounding of abstract mental state concepts in experiential brain systems related to mentalizing, verbal communication and mouth action.

Social Brain Perspectives on the Social and Evolutionary Neuroscience of Human Language

Human language and social cognition are two key disciplines that have traditionally been studied as separate domains. Nonetheless, an emerging view suggests an alternative perspective. Drawing on the theoretical underpinnings of the social brain hypothesis (thesis of the evolution of brain size and intelligence), the social complexity hypothesis (thesis of the evolution of communication), and empirical research from comparative animal behavior, human social behavior, language acquisition in children, social cognitive neuroscience, and the cognitive neuroscience of language, it is argued that social cognition and language are two significantly interconnected capacities of the human species. Here, evidence in support of this view reviews (1) recent developmental studies on language learning in infants and young children, pointing to the important crucial benefits associated with social stimulation for youngsters, including the quality and quantity of incoming linguistic information, dyadic infant/child-to-parent non-verbal and verbal interactions, and other important social cues integral for facilitating language learning and social bonding; (2) studies of the adult human brain, suggesting a high degree of specialization for sociolinguistic information processing, memory retrieval, and comprehension, suggesting that the function of these neural areas may connect social cognition with language and social bonding; (3) developmental deficits in language and social cognition, including autism spectrum disorder (ASD), illustrating a unique developmental profile, further linking language, social cognition, and social bonding; and (4) neural biomarkers that may help to identify early developmental disorders of language and social cognition. In effect, the social brain and social complexity hypotheses may jointly help to describe how neurotypical children and adults acquire language, why autistic children and adults exhibit simultaneous deficits in language and social cognition, and why nonhuman primates and other organisms with significant computational capacities cannot learn language. But perhaps most critically, the following article argues that this and related research will allow scientists to generate a holistic profile and deeper understanding of the healthy adult social brain while developing more innovative and effective diagnoses, prognoses, and treatments for maladies and deficits also associated with the social brain.

Motor experience modulates neural processing of lexical action language: Evidence from rugby players

The perceptual symbol theory proposes a sensorimotor simulation in language processing, emphasizing the role of motor experience. However, the neural basis of motor experience on lexical-level language processing remains little known. In the current fMRI study, we compared brain activation and task-based functional connectivity in 28 rugby players and 28 novices during rugby- specialized and daily verb processing. Distinct differences were observed between the two groups in the bilateral superior temporal gyrus and left angular gyrus regions during specialized verb processing. Notably, intergroup functional connectivity was evident between the left superior temporal gyrus and the right precentral gyrus during specialized verb processing. This study contributes insights into the neural responses and connectivity patterns associated with motor experience at the lexical level, highlighting its potential impact on language processing.

The influence of sentence focus on motor system activity in language comprehension and its temporal dynamics: Preliminary evidence from sEMG

Previous research has shown that individual experiences and experimental tasks can influence the occurrence of mental simulation during sentence comprehension. However, little research has focused on the effect of sentence focus on mental simulation and its temporal dynamics. Sentence focus refers to the hierarchical structure of information within a sentence, where focused information represents the most prominent and essential information. In contrast, nonfocused information provides a background for the focused information. The present study investigated whether sentence focus would affect the activity of the motor system in language comprehension and at which stage the effect of sentence focus occurred. We measured spontaneous arm muscle electrical activity by surface electromyography (sEMG) while participants read action-focused, nonaction-focused, and control sentences. We observed greater spontaneous muscle electrical activity in the flexor common muscle of the fingers when participants read action-focused sentences compared to nonaction-focused and control sentences. Additionally, there was an interactive trend between sentence type and time, spontaneous muscle electrical activity while reading action-focused sentences was observed in both early (1 ms to 300 ms after the presentation of the action phrase) and late time windows (901 ms to 1500 ms after the action phrase). The findings suggest that the motor system exhibits flexible engagement during language comprehension and the impact of sentence focus on motor system activity may be throughout both the lexical-semantic retrieval and sentence-meaning integration stages.

Using agreement probability to study differences in types of concepts and conceptualizers

Agreement probability p(a) is a homogeneity measure of lists of properties produced by participants in a Property Listing Task (PLT) for a concept. Agreement probability's mathematical properties allow a rich analysis of property-based descriptions. To illustrate, we use p(a) to delve into the differences between concrete and abstract concepts in sighted and blind populations. Results show that concrete concepts are more homogeneous within sighted and blind groups than abstract ones (i.e., exhibit a higher p(a) than abstract ones) and that concrete concepts in the blind group are less homogeneous than in the sighted sample. This supports the idea that listed properties for concrete concepts should be more similar across subjects due to the influence of visual/perceptual information on the learning process. In contrast, abstract concepts are learned based mainly on social and linguistic information, which exhibit more variability among people, thus, making the listed properties more dissimilar across subjects. Relative to abstract concepts, the difference in p(a) between sighted and blind is not statistically significant. Though this is a null result, and should be considered with care, it is expected because abstract concepts should be learned by paying attention to the same social and linguistic input in both, blind and sighted, and thus, there is no reason to expect that the respective lists of properties should differ. Finally, we used p(a) to classify concrete and abstract concepts with a good level of certainty. All these analyses suggest that p(a) can be fruitfully used to study data obtained in a PLT.

Breakdown of category-specific word representations in a brain-constrained neurocomputational model of semantic dementia

The neurobiological nature of semantic knowledge, i.e., the encoding and storage of conceptual information in the human brain, remains a poorly understood and hotly debated subject. Clinical data on semantic deficits and neuroimaging evidence from healthy individuals have suggested multiple cortical regions to be involved in the processing of meaning. These include semantic hubs (most notably, anterior temporal lobe, ATL) that take part in semantic processing in general as well as sensorimotor areas that process specific aspects/categories according to their modality. Biologically inspired neurocomputational models can help elucidate the exact roles of these regions in the functioning of the semantic system and, importantly, in its breakdown in neurological deficits. We used a neuroanatomically constrained computational model of frontotemporal cortices implicated in word acquisition and processing, and adapted it to simulate and explain the effects of semantic dementia (SD) on word processing abilities. SD is a devastating, yet insufficiently understood progressive neurodegenerative disease, characterised by semantic knowledge deterioration that is hypothesised to be specifically related to neural damage in the ATL. The behaviour of our brain-based model is in full accordance with clinical data-namely, word comprehension performance decreases as SD lesions in ATL progress, whereas word repetition abilities remain less affected. Furthermore, our model makes predictions about lesion- and category-specific effects of SD: our simulation results indicate that word processing should be more impaired for object- than for action-related words, and that degradation of white matter should produce more severe consequences than the same proportion of grey matter decay. In sum, the present results provide a neuromechanistic explanatory account of cortical-level language impairments observed during the onset and progress of semantic dementia.

Neurobiological mechanisms for language, symbols and concepts: Clues from brain-constrained deep neural networks

Neural networks are successfully used to imitate and model cognitive processes. However, to provide clues about the neurobiological mechanisms enabling human cognition, these models need to mimic the structure and function of real brains. Brain-constrained networks differ from classic neural networks by implementing brain similarities at different scales, ranging from the micro- and mesoscopic levels of neuronal function, local neuronal links and circuit interaction to large-scale anatomical structure and between-area connectivity. This review shows how brain-constrained neural networks can be applied to study in silico the formation of mechanisms for symbol and concept processing and to work towards neurobiological explanations of specifically human cognitive abilities. These include verbal working memory and learning of large vocabularies of symbols, semantic binding carried by specific areas of cortex, attention focusing and modulation driven by symbol type, and the acquisition of concrete and abstract concepts partly influenced by symbols. Neuronal assembly activity in the networks is analyzed to deliver putative mechanistic correlates of higher cognitive processes and to develop candidate explanations founded in established neurobiological principles.

Distinct neurophysiology during nonword repetition in logopenic and non-fluent variants of primary progressive aphasia

Overlapping clinical presentations in primary progressive aphasia (PPA) variants present challenges for diagnosis and understanding pathophysiology, particularly in the early stages of the disease when behavioral (speech) symptoms are not clearly evident. Divergent atrophy patterns (temporoparietal degeneration in logopenic variant lvPPA, frontal degeneration in nonfluent variant nfvPPA) can partially account for differential speech production errors in the two groups in the later stages of the disease. While the existing dogma states that neurodegeneration is the root cause of compromised behavior and cortical activity in PPA, the extent to which neurophysiological signatures of speech dysfunction manifest independent of their divergent atrophy patterns remain unknown. We test the hypothesis that nonword deficits in lvPPA and nfvPPA arise from distinct patterns of neural oscillations that are unrelated to atrophy. We use a novel structure-function imaging approach integrating magnetoencephalographic imaging of neural oscillations during a non-word repetition task with voxel-based morphometry-derived measures of gray matter volume to isolate neural oscillation abnormalities independent of atrophy. We find reduced beta band neural activity in left temporal regions associated with the late stages of auditory encoding unique to patients with lvPPA and reduced high-gamma neural activity over left frontal regions associated with the early stages of motor preparation in patients with nfvPPA. Neither of these patterns of reduced cortical oscillations was explained by cortical atrophy in our statistical model. These findings highlight the importance of structure-function imaging in revealing neurophysiological sequelae in early stages of dementia when neither structural atrophy nor behavioral deficits are clinically distinct.

Concepts require flexible grounding

Research on semantic memory has a problem. On the one hand, a robust body of evidence implicates sensorimotor regions in conceptual processing. On the other hand, a different body of evidence implicates a modality independent semantic system. The standard solution to this tension is to posit a hub-and-spoke system with modality independent hubs and modality specific spokes. In this paper, I argue in support of an alternative view of grounding which remains committed to neural reenactment but emphasizes the multimodal and multilevel nature of the semantic system. This view is built upon the recognition that abstraction is a design feature of concepts. Semantic memory employs hierarchically structured representations to capture different degrees of abstraction. Grounding does not work the way that many embodied approaches have assumed.

Speech comprehension across time, space, frequency, and age: MEG-MVPA classification of intertrial phase coherence

Language is a key part of human cognition, essential for our well-being at all stages of our lives. Whereas many neurocognitive abilities decline with age, for language the picture is much less clear, and how exactly speech comprehension changes with ageing is still unknown. To investigate this, we employed magnetoencephalography (MEG) and recorded neuromagnetic brain responses to auditory linguistic stimuli in healthy participants of younger and older age using a passive task-free paradigm and a range of different linguistic stimulus contrasts, which enabled us to assess neural processing of spoken language at multiple levels (lexical, semantic, morphosyntactic). Using machine learning-based classification algorithms to scrutinise intertrial phase coherence of MEG responses in cortical source space, we found that patterns of oscillatory neural activity diverged between younger and older participants across several frequency bands (alpha, beta, gamma) for all tested linguistic information types. The results suggest multiple age-related changes in the brain's neurolinguistic circuits, which may be due to both healthy ageing in general and compensatory processes in particular.

Hands-On: Investigating the role of physical manipulatives in spatial training

Studies show that spatial interventions lead to improvements in mathematics. However, outcomes vary based on whether physical manipulatives (embodied action) are used during training. This study compares the effects of embodied and non-embodied spatial interventions on spatial and mathematics outcomes. The study has a randomized, controlled, pre-post, follow-up, training design (N = 182; mean age 8 years; 49% female; 83.5% White). We show that both embodied and non-embodied spatial training approaches improve spatial skills compared to control. However, we conclude that embodied spatial training using physical manipulatives leads to larger, more consistent gains in mathematics and greater depth of spatial processing than non-embodied training. These findings highlight the potential of spatial activities, particularly those that use physical materials, for improving children's mathematics skills.

Embodiment of action-related language in the native and a late foreign language - An fMRI-study

Theories of embodied cognition postulate that language processing activates similar sensory-motor structures as when interacting with the environment. Only little is known about the neural substrate of embodiment in a foreign language (L2) as compared to the mother tongue (L1). In this fMRI study, we investigated embodiment of motor and non-motor action verbs in L1 and L2 including 31 late bilinguals. Half had German as L1 and French as L2, and the other half vice-versa. We collapsed across languages to avoid the confound between language and order of language acquisition. Region of interest analyses showed stronger activation in motor regions during L2 than during L1 processing, independently of the motor-relatedness of the verbs. Moreover, a stronger involvement of motor regions for motor-related as compared to non-motor-related verbs, similarly for L1 and L2, was found. Overall, the similarity between L1 and L2 embodiment seems to depend on individual and contextual factors.

Interactions of lexical and conceptual representations: Evidence from EEG

We examined whether meanings automatically activate linguistic forms, and whether these forms affect semantic decisions. Participants were presented sequentially with pairs of pictures and decided whether the objects in the pictures were related. At no point did they name the pictures. The object names of the experimental stimuli were ambiguous either in orthography (homographs), phonology (homophones), or both (homonyms), or unambiguous. We show that the lexical characteristics of the name of the objects affect a semantic decision about real world relations, in an online measure (N400), in addition to offline behavioral measures. We show a dissociation between conceptual and lexical recognition, where an earlier component (N230), was affected by relatedness, but was not sensitive to the lexical characteristics. We interpret this as supporting the hypothesis that semantic recognition occurs before the automatic lexical activation of the object name, but that once linguistic representations are activated, they affect semantic integration.

The cross-linguistic comparison of perceptual strength norms for Korean, English and L2 English

This study aimed to establish perceptual strength norms for 1,000 words in the languages of Korean, English, and L2 English, in order to investigate the similarity and difference across languages as well as the influence of the environment on semantic processing. The perceptual strength norms, which are a collection of word profiles that summarize how a word is experienced through different sensory modalities including the five common senses and interoception, provide a valuable tool for testing embodiment cognition theory. The results of this study demonstrated that language users had parallel sensory experiences with concepts, and that L2 learners were also able to associate their sensory experiences with linguistic concepts. Additionally, the results highlighted the importance of incorporating interoception as a sensory modality in the development of perceptual strength norms, as it had a negative correlation with both vision and concreteness. This study was the first to establish norms for Korean and L2 English and directly compare languages using the identical and translation-equivalent word list.

Scholarly reading (and writing) and the power of impact factors: a study of distributed cognition and intellectual habits

Using observational interviews and introducing theories of embodied and distributed cognition, this study examines the scholarly reading and the intellectual habits of a group of social scientists. All participants were working at universities in task environments dominated by digital artifacts and technologies. The study found a strong connection between scholarly reading and the scholars' writing processes and a further coupling to their digital publishing activity. While examining the participants' print and online reading, it turned out that their reading was so tightly coupled to their writing that this entanglement had to be at the core of the analysis. In the study, scholarly reading and writing are analyzed as cognitive processes that extend beyond the brain and body and comprise cognitive artifacts of texts and their material bearers, such as printouts, digital displays, computers, and the Internet. In the process of creating text-or reading and writing-brains, bodies, and artifacts are considered to be dynamically coupled in a distributed cognitive process. Based on interviews with a sample of academics, the study analyses how their scholarly reading relates to the other elements in such an extended process and how they utilize the affordances of cognitive digital artifacts in their creative and intellectual endeavors.

Sharing Perceptual Experiences through Language

The aim of this article is to shed light on how sensory perceptions are communicated through authentic language. What are the language resources available to match multimodal perceptions, and how do we use them in real communication? We discuss insights from previous work on the topic of the interaction of perception, cognition, and language and explain how language users recontextualise perception in communication about sensory experiences. Within the framework of cognitive semantics, we show that the complexities of multimodal perception are clearly reflected in the multifunctional use of words to convey meanings and feelings. To showcase the language resources employed, we base our findings on research on how architects convey their perceptions of built space. Two main patterns emerge: they use multimodal expressions (soft, bland, and jarring) and descriptions of built space through motion (the building reaches out, or routes and directions such as destination, promenade, route, or landscape in combination with verbs such as start and lead) in which case the architect may either be the observer or the emerged actor. The important take-home message is that there is no neat and clear a priori link between words and meanings, but rather "unforeseen" patterns surface in natural production data describing sensory perceptions.

Bibliometric mapping of non-invasive brain stimulation techniques (NIBS) for fluent speech production

Introduction

Language production is a finely regulated process, with many aspects which still elude comprehension. From a motor perspective, speech involves over a hundred different muscles functioning in coordination. As science and technology evolve, new approaches are used to study speech production and treat its disorders, and there is growing interest in the use of non-invasive modulation by means of transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS).

Methods

Here we analyzed data obtained from Scopus (Elsevier) using VOSViewer to provide an overview of bibliographic mapping of citation, co-occurrence of keywords, co-citation and bibliographic coupling of non-invasive brain stimulation (NIBS) use in speech research.

Results

In total, 253 documents were found, being 55% from only three countries (USA, Germany and Italy), with emerging economies such as Brazil and China becoming relevant in this topic recently. Most documents were published in this last decade, with 2022 being the most productive yet, showing brain stimulation has untapped potential for the speech research field.

Discussion

Keyword analysis indicates a move away from basic research on the motor control in healthy speech, toward clinical applications such as stuttering and aphasia treatment. We also observe a recent trend in cerebellar modulation for clinical treatment. Finally, we discuss how NIBS have established over the years and gained prominence as tools in speech therapy and research, and highlight potential methodological possibilities for future research.

Less is more in language production: an information-theoretic analysis of agrammatism in primary progressive aphasia

Agrammatism is a disorder of language production characterized by short, simplified sentences, the omission of function words, an increased use of nouns over verbs and a higher use of heavy verbs. Despite observing these phenomena for decades, the accounts of agrammatism have not converged. Here, we propose and test the hypothesis that the lexical profile of agrammatism results from a process that opts for words with a lower frequency of occurrence to increase lexical information. Furthermore, we hypothesize that this process is a compensatory response to patients' core deficit in producing long, complex sentences. In this cross-sectional study, we analysed speech samples of patients with primary progressive aphasia (n = 100) and healthy speakers (n = 65) as they described a picture. The patient cohort included 34 individuals with the non-fluent variant, 41 with the logopenic variant and 25 with the semantic variant of primary progressive aphasia. We first analysed a large corpus of spoken language and found that the word types preferred by patients with agrammatism tend to have lower frequencies of occurrence than less preferred words. We then conducted a computational simulation to examine the impact of word frequency on lexical information as measured by entropy. We found that strings of words that exclude highly frequent words have a more uniform word distribution, thereby increasing lexical entropy. To test whether the lexical profile of agrammatism results from their inability to produce long sentences, we asked healthy speakers to produce short sentences during the picture description task. We found that, under this constrained condition, a similar lexical profile of agrammatism emerged in the short sentences of healthy individuals, including fewer function words, more nouns than verbs and more heavy verbs than light verbs. This lexical profile of short sentences resulted in their lower average word frequency than unconstrained sentences. We extended this finding by showing that, in general, shorter sentences get packaged with lower-frequency words as a basic property of efficient language production, evident in the language of healthy speakers and all primary progressive aphasia variants.

The Influence of Emotional Experience on Semantic Processing of Concrete Concepts

Introduction

Parallel distributed processing theory (PDP theory) holds that all brain regions involved in conceptual representation perform a series of activities at the same time. However, the role of emotional experience information in concrete conceptual representation is still unknown. This study further explores whether the emotional experience will also affect the semantic processing of concrete concept representations.

Methods

This study used the emotion priming paradigm and semantic judgment task to explore whether emotion priming impacts the processing of animal concepts with different emotional experiences through two experiments. In Experiments 1a and 1b, pleasant or disgusted faces were used as emotional priming stimuli to explore whether the explicit processing of emotions would affect the semantic processing of animal concepts. Experiments 2a and 2b used positive or negative scenery pictures as emotional priming stimuli to explore whether the implicit processing of emotions would affect the semantic processing of animal concepts.

Results

The Experiment 1 results showed that the perception of faces promotes the processing of animal words, showing the "word-emotion congruence effect". Experiment 2a did not show the expected results, while Experiment 2b showed that the general negative perception of scenery pictures could significantly promote the processing of disgusted animal words. The results further proved the "word-emotion congruence effect" shown in the results of Experiment 1 from the perspective of implicit emotion processing. Combining the results of two experiments, it can be proven that emotional experience affects the semantic processing process of concrete concepts.

Discussion

Both Experiment 1 and Experiment 2b of this study show the "word-emotion congruence effect". PDP theory believes that conceptual representation is represented by the activity patterns of billions of neurons distributed in many areas of the brain, and related semantic processing and sensory processing will occur simultaneously. The results of this experiment well support PDP theory.

Disembodied AI and the limits to machine understanding of students' embodied interactions

The embodiment turn in the Learning Sciences has fueled growth of multimodal learning analytics to understand embodied interactions and make consequential educational decisions about students more rapidly, more accurately, and more personalized than ever before. Managing demands of complexity and speed is leading to growing reliance by education systems on disembodied artificial intelligence (dAI) programs, which, ironically, are inherently incapable of interpreting students' embodied interactions. This is fueling a potential crisis of complexity. Augmented intelligence systems offer promising avenues for managing this crisis by integrating the strengths of omnipresent dAI to detect complex patterns of student behavior from multimodal datastreams, with the strengths of humans to meaningfully interpret embodied interactions in service of consequential decision making to achieve a balance between complexity, interpretability, and accountability for allocating education resources to children.

Gestural Embodiment of Intensifiers in Iconic, Metaphoric, and Beat Gestures

This study aimed to examine the gestural embodiment of intensifiers in iconic and metaphoric gestures when these words are used with literal and metaphoric statements. We asked a group of Persian native speakers to listen to and then retell a set of Persian stories. In these stories, a number of intensifiers were used with literal and metaphoric sentences. The results showed that when an intensifier was used with a literal sentence, there was a higher probability of using an iconic or beat gesture than when there was no intensifier in the sentence. Also, when an intensifier was used with a metaphoric sentence, there was a higher probability of using a metaphoric or beat gesture than when the sentence contained no intensifier. These results suggested that an intensifier in a literal or metaphoric sentence can strengthen the mental simulation and the embodiment of objects, ideas, or situations. When an intensifier is used with a literal or metaphoric sentence, the strength of activation in the premotor areas may be amplified and spread to motor areas. In contrast, when no such intensifier is used in a literal or metaphoric sentence, there is a higher probability of simulation in premotor areas without spreading to the primary motor areas. The production of an internal force and expressing emphasis are two other possibilities that may explain the higher use of gestures with intensifiers.

Abstract concepts and emotion: cross-linguistic evidence and arguments against affective embodiment

How are abstract concepts such as 'freedom' and 'democracy' represented in the mind? One prominent proposal suggests that abstract concepts are grounded in emotion. Supporting this 'affective embodiment' account, abstract concepts are rated to be more strongly positive or more strongly negative than concrete concepts. This paper demonstrates that this finding generalizes across languages by synthesizing rating data from Cantonese, Mandarin Chinese, Croatian, Dutch, French, German, Indonesian, Italian, Polish and Spanish. However, a deeper look at the same data suggests that the idea of emotional grounding only characterizes a small subset of abstract concepts. Moreover, when the concreteness/abstractness dimension is not operationalized using concreteness ratings, it is actually found that concrete concepts are rated as more emotional than abstract ones. Altogether, these results suggest limitations to the idea that emotion is an important factor in the grounding of abstract concepts. This article is part of the theme issue 'Concepts in interaction: social engagement and inner experiences'.

The Impact of Manner Adverb on the Gestural Embodiment of Actions Described by Literal and Metaphoric Sentences

The aim of this study was to examine the impact of manner adverbs on the gestural embodiment of actions that are described by literal and metaphoric sentences. We asked a group of participants to read and then orally retell four stories. Each story had two versions. In one version, literal and metaphoric sentences describing literal and metaphorical actions did not include manner adverbs. In the other version of each story, the same sentences included a manner adverb that provided more information about literal or metaphoric actions. Participants' reproductions of stories were recorded with a camera and were analyzed to make a comparison between gestures that accompanied sentences that included a manner adverb and sentences that did not include a manner adverb. The results showed that when literal and metaphoric sentences included a manner adverb, there was a higher probability of using a gesture than when these sentences were used without a manner adverb. In other words, using a manner adverb increases the probability of using a gesture with literal and metaphorical sentences. Therefore, it is suggested that adding a manner adverb to a literal or metaphoric sentence can strengthen the process of embodiment of the action described in that sentence. We present two explanations for this observation.

Predictive language comprehension in Parkinson's disease

Verb and action knowledge deficits are reported in persons with Parkinson's disease (PD), even in the absence of dementia or mild cognitive impairment. However, the impact of these deficits on combinatorial semantic processing is less well understood. Following on previous verb and action knowledge findings, we tested the hypothesis that PD impairs the ability to integrate event-based thematic fit information during online sentence processing. Specifically, we anticipated persons with PD with age-typical cognitive abilities would perform more poorly than healthy controls during a visual world paradigm task requiring participants to predict a target object constrained by the thematic fit of the agent-verb combination. Twenty-four PD and 24 healthy age-matched participants completed comprehensive neuropsychological assessments. We recorded participants' eye movements as they heard predictive sentences (The fisherman rocks the boat) alongside target, agent-related, verb-related, and unrelated images. We tested effects of group (PD/control) on gaze using growth curve models. There were no significant differences between PD and control participants, suggesting that PD participants successfully and rapidly use combinatory thematic fit information to predict upcoming language. Baseline sentences with no predictive information (e.g., Look at the drum) confirmed that groups showed equivalent sentence processing and eye movement patterns. Additionally, we conducted an exploratory analysis contrasting PD and controls' performance on low-motion-content versus high-motion-content verbs. This analysis revealed fewer predictive fixations in high-motion sentences only for healthy older adults. PD participants may adapt to their disease by relying on spared, non-action-simulation-based language processing mechanisms, although this conclusion is speculative, as the analyses of high- vs. low-motion items was highly limited by the study design. These findings provide novel evidence that individuals with PD match healthy adults in their ability to use verb meaning to predict upcoming nouns despite previous findings of verb semantic impairment in PD across a variety of tasks.

Sequential production of motor-action verb subtypes in Parkinson's disease patients

ABSTRACT Motor-action verbs (MAVs) production and comprehension are compromised in patients with Parkinson's disease (PD). Objectives: The aim of this study was to characterize the sequential production of three subtypes of MAVs in PD patients: whole body (e.g., run), specific body part (e.g., kick), and instrumental (e.g., saw). This study also aimed to identify the production characteristics for each of the two main phases in fluency performance: selection (initial abundant item production) and retrieval (more paced and scarce production). Methods: This study involved a group of 20 nondemented, on-medication PD patients, with an average age of 66.59 years (standard deviation = 4.13), and a comparison group (CG) of 20 normal elderly individuals, matched by years of education and controlled for cognitive performance and depression. Both groups performed a classical verb fluency task. Sequential word-by-word analyses were conducted. Results: Significant differences were found at the initial production of whole-body MAVs and the overall production of instrumental verbs (both measures were lower in the PD group). A repeated-measures analysis of variance confirmed the linear CG performance and the quadratic PD performance. Conclusions: PD patients present altered production of whole-body and instrumental MAVs. This proposal for the semantic sequential analysis of motor verbs deserves further investigation, as a new methodology for the evaluation of fluency performance in motor-related disease.

Motor fluency makes it possible to integrate the components of the trace in memory and facilitates its re-construction

The aim of this work was to test the hypothesis that motor fluency should help the integration of the components of the trace and therefore its re-construction. In the encoding phase of each of the three experiments we conducted, a word to be remembered appeared colored in blue or purple. Participants had to read these words aloud and, at the same time, execute a gesture in their ipsilateral (fluent gesture) or contralateral space (non-fluent gesture), according to the color of the word. The aim of the first experiment was to show that the words associated with a fluent gesture during the encoding phase were more easily recognized than those associated with a non-fluent gesture. The results obtained supported the hypothesis. In the second experiment, our objective was to show that the fluency of a gesture performed during encoding in order to associate a word with a color can facilitate the integration of the word with its color. Here again, the results obtained supported the hypothesis. While in Experiment 2 we tested the effect of motor fluency during encoding on word-color integration, the objective of Experiment 3 was to show that motor fluency was integrated in the word-color trace and contributed to the re-construction of the trace. The results obtained supported the hypothesis. Taken together, these findings lead us to believe that traces are not only traces of the processes that gave rise to them, but also traces of the way in which the processes took place.

Can grammatical morphemes be taught? Evidence of gestures influencing second language procedural learning in middle childhood

What kind of practice makes perfect when children learn to use grammatical morphemes in a second language? Gestures are communicative hand and arm movements which teachers naturally employ as a teaching tool in the classroom. Gesture theory has proposed that gestures package information and previous studies suggest their value for teaching specific items, such as words, as well as abstract systems, such as language. There is broad consensus that implicit learning mechanisms in children are more developed than explicit ones and that everyday use of grammar is implicit and entails developing implicit knowledge. However, while many learners have difficulties acquiring new morpho-syntactic structures, such as the plural{-s} and 3rd person possessive {-s} in English, research on gesture and syntax in middle childhood remains rare. The present study (N = 19) was conducted to better understand if gestures which embody grammatical morphemes during instruction can contribute to procedural learning. Using a novel task, the gesture speeded fragment completion task, our behavioral results show a decrease in mean response times after instruction in the test condition utilizing syntactically specific gestures. This increase in procedural learning suggests that learners in this age group can benefit from embodied instruction in the classroom which visually differentiates between grammatical morphemes which differ in meaning but sound the same.

Gravity matters for the neural representations of action semantics

The dynamic relationship between the neural representation of action word semantics and specific sensorimotor experience remains controversial. Here, we temporarily altered human subjects' sensorimotor experience in a 15-day head-down tilt bed rest setting, a ground-based analog of microgravity that disproportionally affects sensorimotor experiences of the lower limbs, and examined whether such effector-dependent activity deprivation specifically affected the neural processes of comprehending verbs of lower-limb actions (e.g. to kick) relative to upper-limb ones (e.g. to pinch). Using functional magnetic resonance imaging, we compared the multivoxel neural patterns for such action words prior to and after bed rest. We found an effector-specific (lower vs. upper limb) experience modulation in subcortical sensorimotor-related and anterior temporal regions. The neural action semantic representations in other effector-specific verb semantic regions (e.g. left lateral posterior temporal cortex) and motor execution regions were robust against such experience alterations. These effector-specific, sensorimotor-experience-sensitive and experience-independent patterns of verb neural representation highlight the multidimensional and dynamic nature of semantic neural representation, and the broad influence of microgravity (hence gravity) environment on cognition.

Language-related motor facilitation in Italian Sign Language signers

Linguistic tasks facilitate corticospinal excitability as revealed by increased motor evoked potential (MEP) induced by transcranial magnetic stimulation (TMS) in the dominant hand. This modulation of the primary motor cortex (M1) excitability may reflect the relationship between speech and gestures. It is conceivable that in healthy individuals who use a sign language this cortical excitability modulation could be rearranged. The aim of this study was to evaluate the effect of spoken language tasks on M1 excitability in a group of hearing signers. Ten hearing Italian Sign Language (LIS) signers and 16 non-signer healthy controls participated. Single-pulse TMS was applied to either M1 hand area at the baseline and during different tasks: (i) reading aloud, (ii) silent reading, (iii) oral movements, (iv) syllabic phonation and (v) looking at meaningless non-letter strings. Overall, M1 excitability during the linguistic and non-linguistic tasks was higher in LIS group compared to the control group. In LIS group, MEPs were significantly larger during reading aloud, silent reading and non-verbal oral movements, regardless the hemisphere. These results suggest that in hearing signers there is a different modulation of the functional connectivity between the speech-related brain network and the motor system.

Disembodiment and Language in Schizophrenia: An Integrated Psychopathological and Evolutionary Perspective

Different hypotheses have flourished to explain the evolutionary paradox of schizophrenia. In this contribution, we sought to illustrate how, in the schizophrenia spectrum, the concept of embodiment may underpin the phylogenetic and developmental pathways linking sensorimotor processes, the origin of human language, and the construction of a basic sense of the self. In particular, according to an embodied model of language, we suggest that the reuse of basic sensorimotor loops for language, while enabling the development of fully symbolic thought, has pushed the human brain close to the threshold of a severe disruption of self-embodiment processes, which are at the core of schizophrenia psychopathology. We adopted an inter-disciplinary approach (psychopathology, neuroscience, developmental biology) within an evolutionary framework, to gain an integrated, multi-perspectival model on the origin of schizophrenia vulnerability. A maladaptive over-expression of evolutionary-developmental trajectories toward language at the expense of embodiment processes would have led to the evolutionary "trade-off" of a hyper-symbolic activity to the detriment of a disembodied self. Therefore, schizophrenia psychopathology might be the cost of long-term co-evolutive interactions between brain and language.

Targeted neurorehabilitation strategies in post-stroke aphasia

BACKGROUND

Aphasia is a debilitating language impairment, affecting millions of people worldwide. About 40% of stroke survivors develop chronic aphasia, resulting in life-long disability.

OBJECTIVE

This review examines extrinsic and intrinsic neuromodulation techniques, aimed at enhancing the effects of speech and language therapies in stroke survivors with aphasia.

METHODS

We discuss the available evidence supporting the use of transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation, and functional MRI (fMRI) real-time neurofeedback in aphasia rehabilitation.

RESULTS

This review systematically evaluates studies focusing on efficacy and implementation of specialized methods for post-treatment outcome optimization and transfer to functional skills. It considers stimulation target determination and various targeting approaches. The translation of neuromodulation interventions to clinical practice is explored, emphasizing generalization and functional communication. The review also covers real-time fMRI neurofeedback, discussing current evidence for efficacy and essential implementation parameters. Finally, we address future directions for neuromodulation research in aphasia.

CONCLUSIONS

This comprehensive review aims to serve as a resource for a broad audience of researchers and clinicians interested in incorporating neuromodulation for advancing aphasia care.

Experience of memory: transfer of the motor feeling of fluency linked to our interaction with the environment

In the field of memory, it is now admitted that an experience of memory is not only the consequence of the activation of a precise content, but also results from an inference associated with the transfer of the manner in which the process was carried out (i.e., fluency) in addition to the transfer of the process itself. The aim of this work was to show that experience of memory is also associated with the fluency that is due to the transfer of a processing carried out in our past interactions with our environment, independently the fluency associated with the stimulus in progress. First, participants performed a perceptual discrimination task (geometric shapes: circle or square) that involves a fluent or a non-fluent gesture to respond. Motor fluency vs. non-fluency was implicitly associated with the colour of the geometric shapes. Second, participants had to perform a classical memory recognition task. During the recognition phase, items appeared either with the colour associated with motor fluency or with the colour associated with motor non-fluency. We used a Go-NoGo task to avoid having a confused factor (response space). Results show that items were better recognised with a colour associated with motor fluency than with a colour associated with non-motor fluency. These findings support the idea that an experience of memory is also associated with the transfer of the motor feeling of fluency linked to our past interactions with the environment.

Academic training increases grounding of scientific concepts in experiential brain systems

Scientific concepts typically transcendent our sensory experiences. Traditional approaches to science education therefore assume a shift towards amodal or verbal knowledge representations during academic training. Grounded cognition approaches, in contrast, predict a maintenance of grounding of the concepts in experiential brain networks or even an increase. To test these competing approaches, the present study investigated the semantic content of scientific psychological concepts and identified the corresponding neural circuits using functional magnetic resonance imaging (fMRI) in undergraduate psychology students (beginners) and in graduated psychologists (advanced learners). During fMRI scanning, participants were presented with words denoting scientific psychological concepts within a lexical decision task (e.g. "conditioning", "habituation"). The individual semantic property content of each concept was related to brain activity during abstract concept processing. In both beginners and advanced learners, visual and motor properties activated brain regions also involved in perception and action, while mental state properties increased activity in brain regions also recruited by emotional-social scene observation. Only in advanced learners, social constellation properties elicited brain activity overlapping with emotional-social scene observation. In line with grounded cognition approaches, the present results highlight the importance of experiential information for constituting the meaning of abstract scientific concepts during the course of academic training.

Teleporting into walls? The irrelevance of the physical world in embodied perspective-taking

Embodied theories of Level 2 visual perspective-taking usually assume that we imagine ourselves in other real-world locations to take perspectives. We tested this assertion by giving participants an embodied perspective-taking task in which they were instructed to make manual responses based on imagined perspectives. Importantly, on half of the trials, the location of the alternative perspective was not physically possible (i.e., blocked with a wall). Across two experiments, results showed that participants performed just as well for the physically impossible perspectives as for accessible ones. We interpret these data as evidence that embodied perspective-taking is agnostic to local physical features of our environment.